This article explains how the different sections of iExplorer are designed and how to keep a safe and secure backup of your text messages, voicemail, notes, contacts, calendars, and pretty much any other data on your iPhone, iPad, or iPod. The most important thing to understand is that iExplorer, the app itself, does not retain any of your data inside the app or online. It's more of a window showing the data on your device or the data in an iTunes backup on your PC or Mac.
BACKUP SECTION (text messages, voicemail, notes, contacts, etc.)
The Backup section is displaying the data that is within an iTunes backup on your Mac or Windows PC. When you choose Yes to make one in iExplorer or choose to Back Up Now, iExplorer creates a new iTunes backup for you. If you have an existing backup already, iTunes will usually overwrite and incrementally update the previous backup of a device when making a new one where the overwritten/updated data doesn't get moved to the Trash or Recycle Bin, and iExplorer has no control over how iTunes chooses to replace and update older backups. So, before making a new backup (choosing to Back Up Now instead of Use Latest Backup), you'll want to go through each section of iExplorer's Backup section and use the Export buttons to make copies outside of the iTunes backup, especially if you've deleted any data on your iPhone or iPad since the last backup. Most sections have an Export All feature where it will export all of that datatype in a single transfer to a folder on your computer. By default, it will be your Desktop on a PC or your Home folder on a Mac, but you can choose a different folder in the Save As window that appears before a transfer actually begins.
If you are using a Mac, iTunes has a feature to archive any backup which will secure it from ever being overwritten by iTunes. To archive a backup, just open iTunes Preferences and go to the Devices tab. Then, right-click on the backup you want to preserve and choose Archive, and you'll see the current date and time appended to the name of your device. This will protect that backup from being overwritten. This feature is only available in iTunes on a Mac.
MUSIC, PHOTOS, VIDEOS, VOICE MEMOS, iBOOKS, ETC.
All other sections of iExplorer such as Media, Apps, Photos, Media Library, Books, and Root (with Jailbreak) are a direct connection to your device and read the data directly from it without involving an iTunes Backup. So, what you see in iExplorer is only the data that is on the device (like an external monitor for your iPhone, iPad, and iPod). If you want to make copies of it on your computer, be sure to use the Export/Transfer buttons which will copy it to your hard drive.
iExplorer will never remove data from your device during these transfers. It will only copy the data to your computer. The article below explains more:
Is iExplorer safe to use?
Then, for a truly safe backup plan for your personal data, it should always include keeping copies of your data on more than one hard drive in case of hardware failure. While it's rare for a hard drive to stop working and/or lose your data, it's still a definite possibility. Thankfully, external hardware or cloud storage has gotten much cheaper these days, so it doesn't cost much money to keep your data in more than one location as a failsafe. Most cloud storage plans start at only $1 a month now such as Google Drive, iCloud Drive, Dropbox, etc.